The present invention relates to a low cost loop material for a hook and loop fastener having at least one sheet of flexible nonwoven material intermittently bonded to inelastic oriented film. The invention further relates to methods for producing these loops.
Loop fabrics formed by lamination of nonwovens to film are known from, for example, U.S. Pat. No. 5,032,122 which is formed by providing a backing of orientable material in its dimensionally unstable state; positioning a plurality of filaments on the backing; securing the filaments to the backing at spaced, fixed regions along each of the filaments, the fixed regions defining between each pair an unsecured catching region; and causing the orientable material to be transformed along its path of response to its dimensionally stable state thereby shirring the filaments at the catching regions to form fibrous elements projecting from the backing between the fixed regions. U.S. Pat. No. 5,547,531 describes forming a loop fabric by a method comprising the steps of providing a first lamina comprising an elastomeric, pressure-sensitive adhesive film having a first adhesive surface and a second adhesive surface opposed to said first adhesive surface; a relaxed orientation and an elongated orientation; stretching said first lamina from said relaxed orientation to said elongated orientation; contacting a second lamina comprising a nonwoven web with said first surface of said first lamina in said elongated orientation, thereby directly joining said second lamina and said first lamina to form a laminate; and relaxing said first lamina such that said second lamina is shirred to form catching regions capable of entangling the hooks of a complementary male fastening component. U.S. Pat. No. 5,595,567 also uses a nonwoven web which is preferably joined with a backing while the backing is in its elongated unstable orientation. Construction bonds form a bond pattern joining the nonwoven web to the backing. When the backing is contracted from its elongated orientation to its relaxed orientation, the unsecured regions of the nonwoven web become shirred and extend outwardly from the backing to form catching regions that are capable of entangling the engaging elements of a complementary male fastening component. U.S. Pat. No. 5,256,231 describes a method of providing a sheet of loop material adapted to be cut into pieces to form loop portions for fasteners of the type comprising releaseably engageable hook and loop portions and incorporated into items such as disposable garments or diapers. The sheet of loop material includes a sheet of longitudinally oriented fibers having anchor portions and arcuate portions projecting in one direction away from the anchor portions, and a layer of thermoplastic backing material extruded onto the anchor portions to bond to the anchor portions forming at least a portion of a backing for the loop material.
All these methods of forming loops stress the importance of the loop fibers to project outwardly from a backing or base layer. This increases the availability of the fibers to engage suitable hook elements. However, the backings are generally specialized and costly, dimensionally unstable, or thick. It is desired to provide a loop material having projecting loop fibers on a backing that is thin, high strength (dimensionally stable) low cost and easy to manufacture.